Directed by filmmaker Karan Johar's former assistant Karan Malhotra, 'Agneepath' is a remake of the 1990 Hindi film starring Amitabh Bachchan.
In the remake, the villain, played by Sanjay, will be seen as a bald Kancha Cheena, with bulky physique and tattoos on arms.
"I am playing the role of Kancha, a baddie which the film industry will see for the first time. The look in 'Agneepath' will show me in a never-seen-before avatar," Dutt told PTI.
Dutt's look in the film was revealed on his 52nd birthday last week by the producer Karan Johar on twitter.
"I had put on this prosthetic make-up for my character in the film... it used to melt within an hour due to the heat. The temperature was around 48 degrees. We had called this make-up artist from abroad... I used to go mad in that hot temperature. So I thought I better shave off my hair," Dutt said.
The remake will see Hrithik Roshan reprising Bachchan's iconic role of Vijay Deenanath Chauhan, while Priyanka Chopra would be the female lead. The villain, played by Danny Denzongpa in the original, is now being played by Dutt.
"Since I had a couple of other films lined up for release after Agneepath, I could not have shaved off my hair... I had told Karan I will not shave off. But due to the intensity of the heat and the make-up melting, I had to do that," he said.
The remake is set to hit theatres in January.